L-band LDMOS power amplifiers based on an inverse class-F architecture

Two inverse class-F power amplifiers (PAs) working at 1 and 1.8 GHz, respectively, have been developed. The PAs use an LDMOS transistor as an active element in order to generated high efficiency with high output power. The 1-GHz PA achieved a drain efficiency of 77.8% with 12.4 W of output power and the 1.8-GHz PA a drain efficiency of 60% with 13 W of output power. To our knowledge, these results represent the highest efficiency and output power for an inverse class-F PA based on a single LDMOS transistor working at these frequencies.